History will vote Gordon Brown

His time at the top over, Gordon Brown walks out of the pages of newspapers on to those of the history books. How will history judge the man?

The Labour prime minister Brown most resembles is James Callaghan. Both arrived at No 10 after a long wait, succeeding younger, more charismatic men. Neither secured a personal mandate from a general election. Both premierships were dominated by severe financial crises. Each man was far more in tune with the Labour movement and trade unions than their predecessors, and both were moved by moral purpose. They arrived with substantial reputations, though Callaghan, in addition to serving as chancellor, had also been foreign and home secretary, options available to Brown which – unwisely, with hindsight – he chose not to take up. Both declined early elections that they might well have won.

But it will be Tony Blair who Brown will be most closely compared to, a rivalry set to continue in the history books as ferociously as it existed in real life. My guess is that, of these two architects of New Labour, the reputation of Brown's premiership will grow.

True, when it comes to the political skills of leadership, Blair wins, hands down. Where Blair was strong and decisive, Brown agonised. While Blair was charismatic and a natural communicator, Brown was a pessimist who sucked energy out of a room. Blair persisted, but Brown was forced to change direction – over 42 days, the 10p tax rate and Gurkhas. Where Blair was a deft manager of men, Brown was suspicious and awkward, not a team builder, and aggressive under fire. While Blair gave heart to the Labour party and the country at large, Brown never became a natural leader.

But history judges individuals in context. Blair inherited the most fortunate set of circumstances of any Labour PM in history. Like Clement Attlee in 1945 and Harold Wilson in 1966, Blair in 1997 won a landslide victory. But unlike them, he faced an inexperienced opposition front-bench and inherited a strong economy. Blair enjoyed a unified cabinet and Labour movement, an adulatory press and a country eager to support him. By 2007 Brown faced a country growing tired of Labour, the revival of the Tories under David Cameron, and a disillusioned press. He then encountered the worst economic catastrophe since the depression and the expenses crisis.

Blair's domestic achievements were relatively light, given these benefits and 10 years in power. The economic and welfare advances in his first term were principally those of Brown, much the more creative force in those four years, while the constitutional reforms were the legacy of John Smith. Blair would have achieved more after 2001 but for Brown's increasing obduracy. Britain by 2007 had certainly become a more compassionate, open and fairer society, but questions will always be asked whether Blair squandered the promise of 1997, a golden opportunity that may not recur for Labour for another 50 years.

Brown, like Blair, arrived in No 10 with little fixed idea about what he wanted to do domestically. The greatest historical puzzle of the Brown premiership was why a man who had yearned for the job for 13 years did not do more to plan for it. It was Brown's serendipity that the economic crisis that will colour his entire premiership played to his strengths. His handling of it domestically and abroad will receive far more praise than criticism. In contrast, Blair failed on his own big challenge, Iraq. Whether or not Blair was right to commit to the war, history may damn him for his failure to plan for postwar Iraq, taking decisions in such a tight cabal and extracting so little from Bush as the price for British participation. If Blair will have "Iraq" carved on his gravestone, Brown will have his hubristic words about ending "boom and bust".

History will show that Brown achieved more in Northern Ireland, on foreign policy, including deterring India's fury against Pakistan after the Mumbai attacks in 2008, and protecting the most vulnerable, than he was given credit for. His faltering leadership precipitated the plots against him, and the plunge in Labour's poll rating. But he brought Labour back from the brink to achieve 29% of the vote and 258 seats in the election, which denied the Tories a majority, and left Labour much nearer to achieving an unprecedented fourth term government.

Exits from No 10 matter, like John Major calmly going off to the Oval in May 1997. Brown walked away from N0 10 with Sarah, John and Fraser, displaying a magnanimity, as he did when taking the blame for Labour's defeat, which, if exhibited more in power, would have made him the greater leader. But the manner of his exit still earned him respect and sympathy, and these are the tints with which his legacy will be painted; not a great prime minister, but a man of deep intellect and passion whose ambition and temperament often got the better of him, but who served his country with honour and good judgment at a time of grave national crisis.

Anthony Seldon and Guy Lodge's book, Brown at 10, is published in September

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